Add pretty printer for ASAN_MARK and add a helper fn

Add pretty printer for ASAN_MARK and add a helper fn

	* asan.c (asan_mark_poison_p): Remove.
	(asan_mark_p): New function.
	(transform_statements): Use the function.
	(asan_expand_mark_ifn): Do not use masked enum.
	* asan.h (enum asan_mark_flags): Declare it via a macro.
	* gimple-pretty-print.c (dump_gimple_call_args): Dump first
	argument of ASAN_MARK.
	* gimplify.c (build_asan_poison_call_expr): Use new enum values.
	(asan_poison_variable): Likewise.
	* gcc.dg/asan/use-after-scope-goto-1.c: Update first argument of
	scanned pattern ASAN_MARK.
	* gcc.dg/asan/use-after-scope-goto-2.c: Likewise.
	* gcc.dg/asan/use-after-scope-switch-1.c: Likewise.
	* gcc.dg/asan/use-after-scope-switch-2.c: Likewise.
	* gcc.dg/asan/use-after-scope-switch-3.c: Likewise.

From-SVN: r243597